/*
 * Copyright (c) 2014 Redpine Signals Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <linux/etherdevice.h>
#include "rsi_debugfs.h"
#include "rsi_mgmt.h"
#include "rsi_sdio.h"
#include "rsi_common.h"
#include "rsi_ps.h"

static const struct ieee80211_channel rsi_2ghz_channels[] = {
        { .band = NL80211_BAND_2GHZ, .center_freq = 2412,
          .hw_value = 1 }, /* Channel 1 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2417,
          .hw_value = 2 }, /* Channel 2 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2422,
          .hw_value = 3 }, /* Channel 3 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2427,
          .hw_value = 4 }, /* Channel 4 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2432,
          .hw_value = 5 }, /* Channel 5 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2437,
          .hw_value = 6 }, /* Channel 6 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2442,
          .hw_value = 7 }, /* Channel 7 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2447,
          .hw_value = 8 }, /* Channel 8 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2452,
          .hw_value = 9 }, /* Channel 9 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2457,
          .hw_value = 10 }, /* Channel 10 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2462,
          .hw_value = 11 }, /* Channel 11 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2467,
          .hw_value = 12 }, /* Channel 12 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2472,
          .hw_value = 13 }, /* Channel 13 */
        { .band = NL80211_BAND_2GHZ, .center_freq = 2484,
          .hw_value = 14 }, /* Channel 14 */
};

static const struct ieee80211_channel rsi_5ghz_channels[] = {
        { .band = NL80211_BAND_5GHZ, .center_freq = 5180,
          .hw_value = 36,  }, /* Channel 36 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5200,
          .hw_value = 40, }, /* Channel 40 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5220,
          .hw_value = 44, }, /* Channel 44 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5240,
          .hw_value = 48, }, /* Channel 48 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5260,
          .hw_value = 52, }, /* Channel 52 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5280,
          .hw_value = 56, }, /* Channel 56 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5300,
          .hw_value = 60, }, /* Channel 60 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5320,
          .hw_value = 64, }, /* Channel 64 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5500,
          .hw_value = 100, }, /* Channel 100 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5520,
          .hw_value = 104, }, /* Channel 104 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5540,
          .hw_value = 108, }, /* Channel 108 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5560,
          .hw_value = 112, }, /* Channel 112 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5580,
          .hw_value = 116, }, /* Channel 116 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5600,
          .hw_value = 120, }, /* Channel 120 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5620,
          .hw_value = 124, }, /* Channel 124 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5640,
          .hw_value = 128, }, /* Channel 128 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5660,
          .hw_value = 132, }, /* Channel 132 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5680,
          .hw_value = 136, }, /* Channel 136 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5700,
          .hw_value = 140, }, /* Channel 140 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5745,
          .hw_value = 149, }, /* Channel 149 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5765,
          .hw_value = 153, }, /* Channel 153 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5785,
          .hw_value = 157, }, /* Channel 157 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5805,
          .hw_value = 161, }, /* Channel 161 */
        { .band = NL80211_BAND_5GHZ, .center_freq = 5825,
          .hw_value = 165, }, /* Channel 165 */
};

struct ieee80211_rate rsi_rates[12] = {
        { .bitrate = STD_RATE_01  * 5, .hw_value = RSI_RATE_1 },
        { .bitrate = STD_RATE_02  * 5, .hw_value = RSI_RATE_2 },
        { .bitrate = STD_RATE_5_5 * 5, .hw_value = RSI_RATE_5_5 },
        { .bitrate = STD_RATE_11  * 5, .hw_value = RSI_RATE_11 },
        { .bitrate = STD_RATE_06  * 5, .hw_value = RSI_RATE_6 },
        { .bitrate = STD_RATE_09  * 5, .hw_value = RSI_RATE_9 },
        { .bitrate = STD_RATE_12  * 5, .hw_value = RSI_RATE_12 },
        { .bitrate = STD_RATE_18  * 5, .hw_value = RSI_RATE_18 },
        { .bitrate = STD_RATE_24  * 5, .hw_value = RSI_RATE_24 },
        { .bitrate = STD_RATE_36  * 5, .hw_value = RSI_RATE_36 },
        { .bitrate = STD_RATE_48  * 5, .hw_value = RSI_RATE_48 },
        { .bitrate = STD_RATE_54  * 5, .hw_value = RSI_RATE_54 },
};

const u16 rsi_mcsrates[8] = {
        RSI_RATE_MCS0, RSI_RATE_MCS1, RSI_RATE_MCS2, RSI_RATE_MCS3,
        RSI_RATE_MCS4, RSI_RATE_MCS5, RSI_RATE_MCS6, RSI_RATE_MCS7
};

static const u32 rsi_max_ap_stas[16] = {
        32,     /* 1 - Wi-Fi alone */
        0,      /* 2 */
        0,      /* 3 */
        0,      /* 4 - BT EDR alone */
        4,      /* 5 - STA + BT EDR */
        32,     /* 6 - AP + BT EDR */
        0,      /* 7 */
        0,      /* 8 - BT LE alone */
        4,      /* 9 - STA + BE LE */
        0,      /* 10 */
        0,      /* 11 */
        0,      /* 12 */
        1,      /* 13 - STA + BT Dual */
        4,      /* 14 - AP + BT Dual */
};

static const struct ieee80211_iface_limit rsi_iface_limits[] = {
        {
                .max = 1,
                .types = BIT(NL80211_IFTYPE_STATION),
        },
        {
                .max = 1,
                .types = BIT(NL80211_IFTYPE_AP) |
                        BIT(NL80211_IFTYPE_P2P_CLIENT) |
                        BIT(NL80211_IFTYPE_P2P_GO),
        },
        {
                .max = 1,
                .types = BIT(NL80211_IFTYPE_P2P_DEVICE),
        },
};

static const struct ieee80211_iface_combination rsi_iface_combinations[] = {
        {
                .num_different_channels = 1,
                .max_interfaces = 3,
                .limits = rsi_iface_limits,
                .n_limits = ARRAY_SIZE(rsi_iface_limits),
        },
};

/**
 * rsi_is_cipher_wep() -  This function determines if the cipher is WEP or not.
 * @common: Pointer to the driver private structure.
 *
 * Return: If cipher type is WEP, a value of 1 is returned, else 0.
 */

bool rsi_is_cipher_wep(struct rsi_common *common)
{
        if (((common->secinfo.gtk_cipher == WLAN_CIPHER_SUITE_WEP104) ||
             (common->secinfo.gtk_cipher == WLAN_CIPHER_SUITE_WEP40)) &&
            (!common->secinfo.ptk_cipher))
                return true;
        else
                return false;
}

/**
 * rsi_register_rates_channels() - This function registers channels and rates.
 * @adapter: Pointer to the adapter structure.
 * @band: Operating band to be set.
 *
 * Return: int - 0 on success, negative error on failure.
 */
static int rsi_register_rates_channels(struct rsi_hw *adapter, int band)
{
        struct ieee80211_supported_band *sbands = &adapter->sbands[band];
        void *channels = NULL;

        if (band == NL80211_BAND_2GHZ) {
                channels = kmemdup(rsi_2ghz_channels, sizeof(rsi_2ghz_channels),
                                   GFP_KERNEL);
                if (!channels)
                        return -ENOMEM;
                sbands->band = NL80211_BAND_2GHZ;
                sbands->n_channels = ARRAY_SIZE(rsi_2ghz_channels);
                sbands->bitrates = rsi_rates;
                sbands->n_bitrates = ARRAY_SIZE(rsi_rates);
        } else {
                channels = kmemdup(rsi_5ghz_channels, sizeof(rsi_5ghz_channels),
                                   GFP_KERNEL);
                if (!channels)
                        return -ENOMEM;
                sbands->band = NL80211_BAND_5GHZ;
                sbands->n_channels = ARRAY_SIZE(rsi_5ghz_channels);
                sbands->bitrates = &rsi_rates[4];
                sbands->n_bitrates = ARRAY_SIZE(rsi_rates) - 4;
        }

        sbands->channels = channels;

        memset(&sbands->ht_cap, 0, sizeof(struct ieee80211_sta_ht_cap));
        sbands->ht_cap.ht_supported = true;
        sbands->ht_cap.cap = (IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
                              IEEE80211_HT_CAP_SGI_20 |
                              IEEE80211_HT_CAP_SGI_40);
        sbands->ht_cap.ampdu_factor = IEEE80211_HT_MAX_AMPDU_16K;
        sbands->ht_cap.ampdu_density = IEEE80211_HT_MPDU_DENSITY_NONE;
        sbands->ht_cap.mcs.rx_mask[0] = 0xff;
        sbands->ht_cap.mcs.tx_params = IEEE80211_HT_MCS_TX_DEFINED;
        /* sbands->ht_cap.mcs.rx_highest = 0x82; */
        return 0;
}

static int rsi_mac80211_hw_scan_start(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif,
                                      struct ieee80211_scan_request *hw_req)
{
        struct cfg80211_scan_request *scan_req = &hw_req->req;
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct ieee80211_bss_conf *bss = &vif->bss_conf;

        rsi_dbg(INFO_ZONE, "***** Hardware scan start *****\n");
        common->mac_ops_resumed = false;

        if (common->fsm_state != FSM_MAC_INIT_DONE)
                return -ENODEV;

        if ((common->wow_flags & RSI_WOW_ENABLED) ||
            scan_req->n_channels == 0)
                return -EINVAL;

        /* Scan already in progress. So return */
        if (common->bgscan_en)
                return -EBUSY;

        /* If STA is not connected, return with special value 1, in order
         * to start sw_scan in mac80211
         */
        if (!bss->assoc)
                return 1;

        mutex_lock(&common->mutex);
        common->hwscan = scan_req;
        if (!rsi_send_bgscan_params(common, RSI_START_BGSCAN)) {
                if (!rsi_send_bgscan_probe_req(common, vif)) {
                        rsi_dbg(INFO_ZONE, "Background scan started...\n");
                        common->bgscan_en = true;
                }
        }
        mutex_unlock(&common->mutex);

        return 0;
}

static void rsi_mac80211_cancel_hw_scan(struct ieee80211_hw *hw,
                                        struct ieee80211_vif *vif)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct cfg80211_scan_info info;

        rsi_dbg(INFO_ZONE, "***** Hardware scan stop *****\n");
        mutex_lock(&common->mutex);

        if (common->bgscan_en) {
                if (!rsi_send_bgscan_params(common, RSI_STOP_BGSCAN))
                        common->bgscan_en = false;
                info.aborted = false;
                ieee80211_scan_completed(adapter->hw, &info);
                rsi_dbg(INFO_ZONE, "Back ground scan cancelled\n");
        }
        common->hwscan = NULL;
        mutex_unlock(&common->mutex);
}

/**
 * rsi_mac80211_detach() - This function is used to de-initialize the
 *                         Mac80211 stack.
 * @adapter: Pointer to the adapter structure.
 *
 * Return: None.
 */
void rsi_mac80211_detach(struct rsi_hw *adapter)
{
        struct ieee80211_hw *hw = adapter->hw;
        enum nl80211_band band;

        if (hw) {
                ieee80211_stop_queues(hw);
                ieee80211_unregister_hw(hw);
                ieee80211_free_hw(hw);
                adapter->hw = NULL;
        }

        for (band = 0; band < NUM_NL80211_BANDS; band++) {
                struct ieee80211_supported_band *sband =
                                        &adapter->sbands[band];

                kfree(sband->channels);
        }

#ifdef CONFIG_RSI_DEBUGFS
        rsi_remove_dbgfs(adapter);
        kfree(adapter->dfsentry);
#endif
}
EXPORT_SYMBOL_GPL(rsi_mac80211_detach);

/**
 * rsi_indicate_tx_status() - This function indicates the transmit status.
 * @adapter: Pointer to the adapter structure.
 * @skb: Pointer to the socket buffer structure.
 * @status: Status
 *
 * Return: None.
 */
void rsi_indicate_tx_status(struct rsi_hw *adapter,
                            struct sk_buff *skb,
                            int status)
{
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct skb_info *tx_params;

        if (!adapter->hw) {
                rsi_dbg(ERR_ZONE, "##### No MAC #####\n");
                return;
        }

        if (!status)
                info->flags |= IEEE80211_TX_STAT_ACK;

        tx_params = (struct skb_info *)info->driver_data;
        skb_pull(skb, tx_params->internal_hdr_size);
        memset(info->driver_data, 0, IEEE80211_TX_INFO_DRIVER_DATA_SIZE);

        ieee80211_tx_status_irqsafe(adapter->hw, skb);
}

/**
 * rsi_mac80211_tx() - This is the handler that 802.11 module calls for each
 *                     transmitted frame.SKB contains the buffer starting
 *                     from the IEEE 802.11 header.
 * @hw: Pointer to the ieee80211_hw structure.
 * @control: Pointer to the ieee80211_tx_control structure
 * @skb: Pointer to the socket buffer structure.
 *
 * Return: None
 */
static void rsi_mac80211_tx(struct ieee80211_hw *hw,
                            struct ieee80211_tx_control *control,
                            struct sk_buff *skb)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct ieee80211_hdr *wlh = (struct ieee80211_hdr *)skb->data;

        if (ieee80211_is_auth(wlh->frame_control))
                common->mac_ops_resumed = false;

        rsi_core_xmit(common, skb);
}

/**
 * rsi_mac80211_start() - This is first handler that 802.11 module calls, since
 *                        the driver init is complete by then, just
 *                        returns success.
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: 0 as success.
 */
static int rsi_mac80211_start(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        rsi_dbg(ERR_ZONE, "===> Interface UP <===\n");
        mutex_lock(&common->mutex);
        if (common->hibernate_resume) {
                common->reinit_hw = true;
                adapter->host_intf_ops->reinit_device(adapter);
                wait_for_completion(&adapter->priv->wlan_init_completion);
        }
        common->iface_down = false;
        wiphy_rfkill_start_polling(hw->wiphy);
        rsi_send_rx_filter_frame(common, 0);
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_mac80211_stop() - This is the last handler that 802.11 module calls.
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: None.
 */
static void rsi_mac80211_stop(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        rsi_dbg(ERR_ZONE, "===> Interface DOWN <===\n");
        mutex_lock(&common->mutex);
        common->iface_down = true;
        wiphy_rfkill_stop_polling(hw->wiphy);

        /* Block all rx frames */
        rsi_send_rx_filter_frame(common, 0xffff);

        mutex_unlock(&common->mutex);
}

static int rsi_map_intf_mode(enum nl80211_iftype vif_type)
{
        switch (vif_type) {
        case NL80211_IFTYPE_STATION:
                return RSI_OPMODE_STA;
        case NL80211_IFTYPE_AP:
                return RSI_OPMODE_AP;
        case NL80211_IFTYPE_P2P_DEVICE:
                return RSI_OPMODE_P2P_CLIENT;
        case NL80211_IFTYPE_P2P_CLIENT:
                return RSI_OPMODE_P2P_CLIENT;
        case NL80211_IFTYPE_P2P_GO:
                return RSI_OPMODE_P2P_GO;
        default:
                return RSI_OPMODE_UNSUPPORTED;
        }
}

/**
 * rsi_mac80211_add_interface() - This function is called when a netdevice
 *                                attached to the hardware is enabled.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 *
 * Return: ret: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_add_interface(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct vif_priv *vif_info = (struct vif_priv *)vif->drv_priv;
        enum opmode intf_mode;
        enum vap_status vap_status;
        int vap_idx = -1, i;

        vif->driver_flags |= IEEE80211_VIF_SUPPORTS_UAPSD;
        mutex_lock(&common->mutex);

        intf_mode = rsi_map_intf_mode(vif->type);
        if (intf_mode == RSI_OPMODE_UNSUPPORTED) {
                rsi_dbg(ERR_ZONE,
                        "%s: Interface type %d not supported\n", __func__,
                        vif->type);
                mutex_unlock(&common->mutex);
                return -EOPNOTSUPP;
        }
        if ((vif->type == NL80211_IFTYPE_P2P_DEVICE) ||
            (vif->type == NL80211_IFTYPE_P2P_CLIENT) ||
            (vif->type == NL80211_IFTYPE_P2P_GO))
                common->p2p_enabled = true;

        /* Get free vap index */
        for (i = 0; i < RSI_MAX_VIFS; i++) {
                if (!adapter->vifs[i] ||
                    !memcmp(vif->addr, adapter->vifs[i]->addr, ETH_ALEN)) {
                        vap_idx = i;
                        break;
                }
        }
        if (vap_idx < 0) {
                rsi_dbg(ERR_ZONE, "Reject: Max VAPs reached\n");
                mutex_unlock(&common->mutex);
                return -EOPNOTSUPP;
        }
        vif_info->vap_id = vap_idx;
        adapter->vifs[vap_idx] = vif;
        adapter->sc_nvifs++;
        vap_status = VAP_ADD;

        if (rsi_set_vap_capabilities(common, intf_mode, vif->addr,
                                     vif_info->vap_id, vap_status)) {
                rsi_dbg(ERR_ZONE, "Failed to set VAP capabilities\n");
                mutex_unlock(&common->mutex);
                return -EINVAL;
        }

        if ((vif->type == NL80211_IFTYPE_AP) ||
            (vif->type == NL80211_IFTYPE_P2P_GO)) {
                rsi_send_rx_filter_frame(common, DISALLOW_BEACONS);
                common->min_rate = RSI_RATE_AUTO;
                for (i = 0; i < common->max_stations; i++)
                        common->stations[i].sta = NULL;
        }

        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_mac80211_remove_interface() - This function notifies driver that an
 *                                   interface is going down.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 *
 * Return: None.
 */
static void rsi_mac80211_remove_interface(struct ieee80211_hw *hw,
                                          struct ieee80211_vif *vif)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        enum opmode opmode;
        int i;

        rsi_dbg(INFO_ZONE, "Remove Interface Called\n");

        mutex_lock(&common->mutex);

        if (adapter->sc_nvifs <= 0) {
                mutex_unlock(&common->mutex);
                return;
        }

        opmode = rsi_map_intf_mode(vif->type);
        if (opmode == RSI_OPMODE_UNSUPPORTED) {
                rsi_dbg(ERR_ZONE, "Opmode error : %d\n", opmode);
                mutex_unlock(&common->mutex);
                return;
        }
        for (i = 0; i < RSI_MAX_VIFS; i++) {
                if (!adapter->vifs[i])
                        continue;
                if (vif == adapter->vifs[i]) {
                        rsi_set_vap_capabilities(common, opmode, vif->addr,
                                                 i, VAP_DELETE);
                        adapter->sc_nvifs--;
                        adapter->vifs[i] = NULL;
                }
        }
        mutex_unlock(&common->mutex);
}

/**
 * rsi_channel_change() - This function is a performs the checks
 *                        required for changing a channel and sets
 *                        the channel accordingly.
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_channel_change(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        int status = -EOPNOTSUPP;
        struct ieee80211_channel *curchan = hw->conf.chandef.chan;
        u16 channel = curchan->hw_value;
        struct ieee80211_vif *vif;
        struct ieee80211_bss_conf *bss;
        bool assoc = false;
        int i;

        rsi_dbg(INFO_ZONE,
                "%s: Set channel: %d MHz type: %d channel_no %d\n",
                __func__, curchan->center_freq,
                curchan->flags, channel);

        for (i = 0; i < RSI_MAX_VIFS; i++) {
                vif = adapter->vifs[i];
                if (!vif)
                        continue;
                if (vif->type == NL80211_IFTYPE_STATION) {
                        bss = &vif->bss_conf;
                        if (bss->assoc) {
                                assoc = true;
                                break;
                        }
                }
        }
        if (assoc) {
                if (!common->hw_data_qs_blocked &&
                    (rsi_get_connected_channel(vif) != channel)) {
                        rsi_dbg(INFO_ZONE, "blk data q %d\n", channel);
                        if (!rsi_send_block_unblock_frame(common, true))
                                common->hw_data_qs_blocked = true;
                }
        }

        status = rsi_band_check(common, curchan);
        if (!status)
                status = rsi_set_channel(adapter->priv, curchan);

        if (assoc) {
                if (common->hw_data_qs_blocked &&
                    (rsi_get_connected_channel(vif) == channel)) {
                        rsi_dbg(INFO_ZONE, "unblk data q %d\n", channel);
                        if (!rsi_send_block_unblock_frame(common, false))
                                common->hw_data_qs_blocked = false;
                }
        }

        return status;
}

/**
 * rsi_config_power() - This function configures tx power to device
 * @hw: Pointer to the ieee80211_hw structure.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_config_power(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct ieee80211_conf *conf = &hw->conf;

        if (adapter->sc_nvifs <= 0) {
                rsi_dbg(ERR_ZONE, "%s: No virtual interface found\n", __func__);
                return -EINVAL;
        }

        rsi_dbg(INFO_ZONE,
                "%s: Set tx power: %d dBM\n", __func__, conf->power_level);

        if (conf->power_level == common->tx_power)
                return 0;

        common->tx_power = conf->power_level;

        return rsi_send_radio_params_update(common);
}

/**
 * rsi_mac80211_config() - This function is a handler for configuration
 *                         requests. The stack calls this function to
 *                         change hardware configuration, e.g., channel.
 * @hw: Pointer to the ieee80211_hw structure.
 * @changed: Changed flags set.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_config(struct ieee80211_hw *hw,
                               u32 changed)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct ieee80211_conf *conf = &hw->conf;
        int status = -EOPNOTSUPP;

        mutex_lock(&common->mutex);

        if (changed & IEEE80211_CONF_CHANGE_CHANNEL)
                status = rsi_channel_change(hw);

        /* tx power */
        if (changed & IEEE80211_CONF_CHANGE_POWER) {
                rsi_dbg(INFO_ZONE, "%s: Configuring Power\n", __func__);
                status = rsi_config_power(hw);
        }

        /* Power save parameters */
        if ((changed & IEEE80211_CONF_CHANGE_PS) &&
            !common->mac_ops_resumed) {
                struct ieee80211_vif *vif, *sta_vif = NULL;
                unsigned long flags;
                int i, set_ps = 1;

                for (i = 0; i < RSI_MAX_VIFS; i++) {
                        vif = adapter->vifs[i];
                        if (!vif)
                                continue;
                        /* Don't go to power save if AP vap exists */
                        if ((vif->type == NL80211_IFTYPE_AP) ||
                            (vif->type == NL80211_IFTYPE_P2P_GO)) {
                                set_ps = 0;
                                break;
                        }
                        if ((vif->type == NL80211_IFTYPE_STATION ||
                             vif->type == NL80211_IFTYPE_P2P_CLIENT) &&
                            (!sta_vif || vif->bss_conf.assoc))
                                sta_vif = vif;
                }
                if (set_ps && sta_vif) {
                        spin_lock_irqsave(&adapter->ps_lock, flags);
                        if (conf->flags & IEEE80211_CONF_PS)
                                rsi_enable_ps(adapter, sta_vif);
                        else
                                rsi_disable_ps(adapter, sta_vif);
                        spin_unlock_irqrestore(&adapter->ps_lock, flags);
                }
        }

        /* RTS threshold */
        if (changed & WIPHY_PARAM_RTS_THRESHOLD) {
                rsi_dbg(INFO_ZONE, "RTS threshold\n");
                if ((common->rts_threshold) <= IEEE80211_MAX_RTS_THRESHOLD) {
                        rsi_dbg(INFO_ZONE,
                                "%s: Sending vap updates....\n", __func__);
                        status = rsi_send_vap_dynamic_update(common);
                }
        }
        mutex_unlock(&common->mutex);

        return status;
}

/**
 * rsi_get_connected_channel() - This function is used to get the current
 *                               connected channel number.
 * @vif: Pointer to the ieee80211_vif structure.
 *
 * Return: Current connected AP's channel number is returned.
 */
u16 rsi_get_connected_channel(struct ieee80211_vif *vif)
{
        struct ieee80211_bss_conf *bss;
        struct ieee80211_channel *channel;

        if (!vif)
                return 0;

        bss = &vif->bss_conf;
        channel = bss->chandef.chan;

        if (!channel)
                return 0;

        return channel->hw_value;
}

static void rsi_switch_channel(struct rsi_hw *adapter,
                               struct ieee80211_vif *vif)
{
        struct rsi_common *common = adapter->priv;
        struct ieee80211_channel *channel;

        if (common->iface_down)
                return;
        if (!vif)
                return;

        channel = vif->bss_conf.chandef.chan;

        if (!channel)
                return;

        rsi_band_check(common, channel);
        rsi_set_channel(common, channel);
        rsi_dbg(INFO_ZONE, "Switched to channel - %d\n", channel->hw_value);
}

/**
 * rsi_mac80211_bss_info_changed() - This function is a handler for config
 *                                   requests related to BSS parameters that
 *                                   may vary during BSS's lifespan.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @bss_conf: Pointer to the ieee80211_bss_conf structure.
 * @changed: Changed flags set.
 *
 * Return: None.
 */
static void rsi_mac80211_bss_info_changed(struct ieee80211_hw *hw,
                                          struct ieee80211_vif *vif,
                                          struct ieee80211_bss_conf *bss_conf,
                                          u32 changed)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct ieee80211_bss_conf *bss = &vif->bss_conf;
        struct ieee80211_conf *conf = &hw->conf;
        u16 rx_filter_word = 0;

        mutex_lock(&common->mutex);
        if (changed & BSS_CHANGED_ASSOC) {
                rsi_dbg(INFO_ZONE, "%s: Changed Association status: %d\n",
                        __func__, bss_conf->assoc);
                if (bss_conf->assoc) {
                        /* Send the RX filter frame */
                        rx_filter_word = (ALLOW_DATA_ASSOC_PEER |
                                          ALLOW_CTRL_ASSOC_PEER |
                                          ALLOW_MGMT_ASSOC_PEER);
                        rsi_send_rx_filter_frame(common, rx_filter_word);
                }
                rsi_inform_bss_status(common,
                                      RSI_OPMODE_STA,
                                      bss_conf->assoc,
                                      bss_conf->bssid,
                                      bss_conf->qos,
                                      bss_conf->aid,
                                      NULL, 0,
                                      bss_conf->assoc_capability, vif);
                adapter->ps_info.dtim_interval_duration = bss->dtim_period;
                adapter->ps_info.listen_interval = conf->listen_interval;

                /* If U-APSD is updated, send ps parameters to firmware */
                if (bss->assoc) {
                        if (common->uapsd_bitmap) {
                                rsi_dbg(INFO_ZONE, "Configuring UAPSD\n");
                                rsi_conf_uapsd(adapter, vif);
                        }
                } else {
                        common->uapsd_bitmap = 0;
                }
        }

        if (changed & BSS_CHANGED_CQM) {
                common->cqm_info.last_cqm_event_rssi = 0;
                common->cqm_info.rssi_thold = bss_conf->cqm_rssi_thold;
                common->cqm_info.rssi_hyst = bss_conf->cqm_rssi_hyst;
                rsi_dbg(INFO_ZONE, "RSSI threshold & hysteresis are: %d %d\n",
                        common->cqm_info.rssi_thold,
                        common->cqm_info.rssi_hyst);
        }

        if (changed & BSS_CHANGED_BEACON_INT) {
                rsi_dbg(INFO_ZONE, "%s: Changed Beacon interval: %d\n",
                        __func__, bss_conf->beacon_int);
                if (common->beacon_interval != bss->beacon_int) {
                        common->beacon_interval = bss->beacon_int;
                        if (vif->type == NL80211_IFTYPE_AP) {
                                struct vif_priv *vif_info = (struct vif_priv *)vif->drv_priv;

                                rsi_set_vap_capabilities(common, RSI_OPMODE_AP,
                                                         vif->addr, vif_info->vap_id,
                                                         VAP_UPDATE);
                        }
                }
                adapter->ps_info.listen_interval =
                        bss->beacon_int * adapter->ps_info.num_bcns_per_lis_int;
        }

        if ((changed & BSS_CHANGED_BEACON_ENABLED) &&
            ((vif->type == NL80211_IFTYPE_AP) ||
             (vif->type == NL80211_IFTYPE_P2P_GO))) {
                if (bss->enable_beacon) {
                        rsi_dbg(INFO_ZONE, "===> BEACON ENABLED <===\n");
                        common->beacon_enabled = 1;
                } else {
                        rsi_dbg(INFO_ZONE, "===> BEACON DISABLED <===\n");
                        common->beacon_enabled = 0;
                }
        }

        mutex_unlock(&common->mutex);
}

/**
 * rsi_mac80211_conf_filter() - This function configure the device's RX filter.
 * @hw: Pointer to the ieee80211_hw structure.
 * @changed_flags: Changed flags set.
 * @total_flags: Total initial flags set.
 * @multicast: Multicast.
 *
 * Return: None.
 */
static void rsi_mac80211_conf_filter(struct ieee80211_hw *hw,
                                     u32 changed_flags,
                                     u32 *total_flags,
                                     u64 multicast)
{
        /* Not doing much here as of now */
        *total_flags &= RSI_SUPP_FILTERS;
}

/**
 * rsi_mac80211_conf_tx() - This function configures TX queue parameters
 *                          (EDCF (aifs, cw_min, cw_max), bursting)
 *                          for a hardware TX queue.
 * @hw: Pointer to the ieee80211_hw structure
 * @vif: Pointer to the ieee80211_vif structure.
 * @queue: Queue number.
 * @params: Pointer to ieee80211_tx_queue_params structure.
 *
 * Return: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_conf_tx(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif, u16 queue,
                                const struct ieee80211_tx_queue_params *params)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        u8 idx = 0;

        if (queue >= IEEE80211_NUM_ACS)
                return 0;

        rsi_dbg(INFO_ZONE,
                "%s: Conf queue %d, aifs: %d, cwmin: %d cwmax: %d, txop: %d\n",
                __func__, queue, params->aifs,
                params->cw_min, params->cw_max, params->txop);

        mutex_lock(&common->mutex);
        /* Map into the way the f/w expects */
        switch (queue) {
        case IEEE80211_AC_VO:
                idx = VO_Q;
                break;
        case IEEE80211_AC_VI:
                idx = VI_Q;
                break;
        case IEEE80211_AC_BE:
                idx = BE_Q;
                break;
        case IEEE80211_AC_BK:
                idx = BK_Q;
                break;
        default:
                idx = BE_Q;
                break;
        }

        memcpy(&common->edca_params[idx],
               params,
               sizeof(struct ieee80211_tx_queue_params));

        if (params->uapsd)
                common->uapsd_bitmap |= idx;
        else
                common->uapsd_bitmap &= (~idx);

        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_hal_key_config() - This function loads the keys into the firmware.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @key: Pointer to the ieee80211_key_conf structure.
 * @sta: Pointer to the ieee80211_sta structure.
 *
 * Return: status: 0 on success, negative error codes on failure.
 */
static int rsi_hal_key_config(struct ieee80211_hw *hw,
                              struct ieee80211_vif *vif,
                              struct ieee80211_key_conf *key,
                              struct ieee80211_sta *sta)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_sta *rsta = NULL;
        int status;
        u8 key_type;
        s16 sta_id = 0;

        if (key->flags & IEEE80211_KEY_FLAG_PAIRWISE)
                key_type = RSI_PAIRWISE_KEY;
        else
                key_type = RSI_GROUP_KEY;

        rsi_dbg(ERR_ZONE, "%s: Cipher 0x%x key_type: %d key_len: %d\n",
                __func__, key->cipher, key_type, key->keylen);

        if ((vif->type == NL80211_IFTYPE_AP) ||
            (vif->type == NL80211_IFTYPE_P2P_GO)) {
                if (sta) {
                        rsta = rsi_find_sta(adapter->priv, sta->addr);
                        if (rsta)
                                sta_id = rsta->sta_id;
                }
                adapter->priv->key = key;
        } else {
                if ((key->cipher == WLAN_CIPHER_SUITE_WEP104) ||
                    (key->cipher == WLAN_CIPHER_SUITE_WEP40)) {
                        status = rsi_hal_load_key(adapter->priv,
                                                  key->key,
                                                  key->keylen,
                                                  RSI_PAIRWISE_KEY,
                                                  key->keyidx,
                                                  key->cipher,
                                                  sta_id,
                                                  vif);
                        if (status)
                                return status;
                }

        }

        status = rsi_hal_load_key(adapter->priv,
                                  key->key,
                                  key->keylen,
                                  key_type,
                                  key->keyidx,
                                  key->cipher,
                                  sta_id,
                                  vif);
        if (status)
                return status;

        if (vif->type == NL80211_IFTYPE_STATION &&
            (key->cipher == WLAN_CIPHER_SUITE_WEP104 ||
             key->cipher == WLAN_CIPHER_SUITE_WEP40)) {
                if (!rsi_send_block_unblock_frame(adapter->priv, false))
                        adapter->priv->hw_data_qs_blocked = false;
        }

        return 0;
}

/**
 * rsi_mac80211_set_key() - This function sets type of key to be loaded.
 * @hw: Pointer to the ieee80211_hw structure.
 * @cmd: enum set_key_cmd.
 * @vif: Pointer to the ieee80211_vif structure.
 * @sta: Pointer to the ieee80211_sta structure.
 * @key: Pointer to the ieee80211_key_conf structure.
 *
 * Return: status: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_set_key(struct ieee80211_hw *hw,
                                enum set_key_cmd cmd,
                                struct ieee80211_vif *vif,
                                struct ieee80211_sta *sta,
                                struct ieee80211_key_conf *key)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct security_info *secinfo = &common->secinfo;
        int status;

        mutex_lock(&common->mutex);
        switch (cmd) {
        case SET_KEY:
                status = rsi_hal_key_config(hw, vif, key, sta);
                if (status) {
                        mutex_unlock(&common->mutex);
                        return status;
                }

                if (key->flags & IEEE80211_KEY_FLAG_PAIRWISE)
                        secinfo->ptk_cipher = key->cipher;
                else
                        secinfo->gtk_cipher = key->cipher;

                key->hw_key_idx = key->keyidx;
                key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;

                rsi_dbg(ERR_ZONE, "%s: RSI set_key\n", __func__);
                break;

        case DISABLE_KEY:
                rsi_dbg(ERR_ZONE, "%s: RSI del key\n", __func__);
                memset(key, 0, sizeof(struct ieee80211_key_conf));
                status = rsi_hal_key_config(hw, vif, key, sta);
                break;

        default:
                status = -EOPNOTSUPP;
                break;
        }

        mutex_unlock(&common->mutex);
        return status;
}

/**
 * rsi_mac80211_ampdu_action() - This function selects the AMPDU action for
 *                               the corresponding mlme_action flag and
 *                               informs the f/w regarding this.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @params: Pointer to A-MPDU action parameters
 *
 * Return: status: 0 on success, negative error code on failure.
 */
static int rsi_mac80211_ampdu_action(struct ieee80211_hw *hw,
                                     struct ieee80211_vif *vif,
                                     struct ieee80211_ampdu_params *params)
{
        int status = -EOPNOTSUPP;
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct rsi_sta *rsta = NULL;
        u16 seq_no = 0, seq_start = 0;
        u8 ii = 0;
        struct ieee80211_sta *sta = params->sta;
        u8 sta_id = 0;
        enum ieee80211_ampdu_mlme_action action = params->action;
        u16 tid = params->tid;
        u16 *ssn = &params->ssn;
        u8 buf_size = params->buf_size;

        for (ii = 0; ii < RSI_MAX_VIFS; ii++) {
                if (vif == adapter->vifs[ii])
                        break;
        }

        mutex_lock(&common->mutex);

        if (ssn != NULL)
                seq_no = *ssn;

        if ((vif->type == NL80211_IFTYPE_AP) ||
            (vif->type == NL80211_IFTYPE_P2P_GO)) {
                rsta = rsi_find_sta(common, sta->addr);
                if (!rsta) {
                        rsi_dbg(ERR_ZONE, "No station mapped\n");
                        status = 0;
                        goto unlock;
                }
                sta_id = rsta->sta_id;
        }

        rsi_dbg(INFO_ZONE,
                "%s: AMPDU action tid=%d ssn=0x%x, buf_size=%d sta_id=%d\n",
                __func__, tid, seq_no, buf_size, sta_id);

        switch (action) {
        case IEEE80211_AMPDU_RX_START:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           seq_no,
                                                           buf_size,
                                                           STA_RX_ADDBA_DONE,
                                                           sta_id);
                break;

        case IEEE80211_AMPDU_RX_STOP:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           0,
                                                           buf_size,
                                                           STA_RX_DELBA,
                                                           sta_id);
                break;

        case IEEE80211_AMPDU_TX_START:
                if ((vif->type == NL80211_IFTYPE_STATION) ||
                    (vif->type == NL80211_IFTYPE_P2P_CLIENT))
                        common->vif_info[ii].seq_start = seq_no;
                else if ((vif->type == NL80211_IFTYPE_AP) ||
                         (vif->type == NL80211_IFTYPE_P2P_GO))
                        rsta->seq_start[tid] = seq_no;
                status = IEEE80211_AMPDU_TX_START_IMMEDIATE;
                break;

        case IEEE80211_AMPDU_TX_STOP_CONT:
        case IEEE80211_AMPDU_TX_STOP_FLUSH:
        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           seq_no,
                                                           buf_size,
                                                           STA_TX_DELBA,
                                                           sta_id);
                if (!status)
                        ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                break;

        case IEEE80211_AMPDU_TX_OPERATIONAL:
                if ((vif->type == NL80211_IFTYPE_STATION) ||
                    (vif->type == NL80211_IFTYPE_P2P_CLIENT))
                        seq_start = common->vif_info[ii].seq_start;
                else if ((vif->type == NL80211_IFTYPE_AP) ||
                         (vif->type == NL80211_IFTYPE_P2P_GO))
                        seq_start = rsta->seq_start[tid];
                status = rsi_send_aggregation_params_frame(common,
                                                           tid,
                                                           seq_start,
                                                           buf_size,
                                                           STA_TX_ADDBA_DONE,
                                                           sta_id);
                break;

        default:
                rsi_dbg(ERR_ZONE, "%s: Unknown AMPDU action\n", __func__);
                break;
        }

unlock:
        mutex_unlock(&common->mutex);
        return status;
}

/**
 * rsi_mac80211_set_rts_threshold() - This function sets rts threshold value.
 * @hw: Pointer to the ieee80211_hw structure.
 * @value: Rts threshold value.
 *
 * Return: 0 on success.
 */
static int rsi_mac80211_set_rts_threshold(struct ieee80211_hw *hw,
                                          u32 value)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        common->rts_threshold = value;
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_mac80211_set_rate_mask() - This function sets bitrate_mask to be used.
 * @hw: Pointer to the ieee80211_hw structure
 * @vif: Pointer to the ieee80211_vif structure.
 * @mask: Pointer to the cfg80211_bitrate_mask structure.
 *
 * Return: 0 on success.
 */
static int rsi_mac80211_set_rate_mask(struct ieee80211_hw *hw,
                                      struct ieee80211_vif *vif,
                                      const struct cfg80211_bitrate_mask *mask)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        enum nl80211_band band = hw->conf.chandef.chan->band;

        mutex_lock(&common->mutex);
        common->fixedrate_mask[band] = 0;

        if (mask->control[band].legacy == 0xfff) {
                common->fixedrate_mask[band] =
                        (mask->control[band].ht_mcs[0] << 12);
        } else {
                common->fixedrate_mask[band] =
                        mask->control[band].legacy;
        }
        mutex_unlock(&common->mutex);

        return 0;
}

/**
 * rsi_perform_cqm() - This function performs cqm.
 * @common: Pointer to the driver private structure.
 * @bssid: pointer to the bssid.
 * @rssi: RSSI value.
 * @vif: Pointer to the ieee80211_vif structure.
 */
static void rsi_perform_cqm(struct rsi_common *common,
                            u8 *bssid,
                            s8 rssi,
                            struct ieee80211_vif *vif)
{
        s8 last_event = common->cqm_info.last_cqm_event_rssi;
        int thold = common->cqm_info.rssi_thold;
        u32 hyst = common->cqm_info.rssi_hyst;
        enum nl80211_cqm_rssi_threshold_event event;

        if (rssi < thold && (last_event == 0 || rssi < (last_event - hyst)))
                event = NL80211_CQM_RSSI_THRESHOLD_EVENT_LOW;
        else if (rssi > thold &&
                 (last_event == 0 || rssi > (last_event + hyst)))
                event = NL80211_CQM_RSSI_THRESHOLD_EVENT_HIGH;
        else
                return;

        common->cqm_info.last_cqm_event_rssi = rssi;
        rsi_dbg(INFO_ZONE, "CQM: Notifying event: %d\n", event);
        ieee80211_cqm_rssi_notify(vif, event, rssi, GFP_KERNEL);

        return;
}

/**
 * rsi_fill_rx_status() - This function fills rx status in
 *                        ieee80211_rx_status structure.
 * @hw: Pointer to the ieee80211_hw structure.
 * @skb: Pointer to the socket buffer structure.
 * @common: Pointer to the driver private structure.
 * @rxs: Pointer to the ieee80211_rx_status structure.
 *
 * Return: None.
 */
static void rsi_fill_rx_status(struct ieee80211_hw *hw,
                               struct sk_buff *skb,
                               struct rsi_common *common,
                               struct ieee80211_rx_status *rxs)
{
        struct rsi_hw *adapter = common->priv;
        struct ieee80211_vif *vif;
        struct ieee80211_bss_conf *bss = NULL;
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct skb_info *rx_params = (struct skb_info *)info->driver_data;
        struct ieee80211_hdr *hdr;
        char rssi = rx_params->rssi;
        u8 hdrlen = 0;
        u8 channel = rx_params->channel;
        s32 freq;
        int i;

        hdr = ((struct ieee80211_hdr *)(skb->data));
        hdrlen = ieee80211_hdrlen(hdr->frame_control);

        memset(info, 0, sizeof(struct ieee80211_tx_info));

        rxs->signal = -(rssi);

        rxs->band = common->band;

        freq = ieee80211_channel_to_frequency(channel, rxs->band);

        if (freq)
                rxs->freq = freq;

        if (ieee80211_has_protected(hdr->frame_control)) {
                if (rsi_is_cipher_wep(common)) {
                        memmove(skb->data + 4, skb->data, hdrlen);
                        skb_pull(skb, 4);
                } else {
                        memmove(skb->data + 8, skb->data, hdrlen);
                        skb_pull(skb, 8);
                        rxs->flag |= RX_FLAG_MMIC_STRIPPED;
                }
                rxs->flag |= RX_FLAG_DECRYPTED;
                rxs->flag |= RX_FLAG_IV_STRIPPED;
        }

        for (i = 0; i < RSI_MAX_VIFS; i++) {
                vif = adapter->vifs[i];
                if (!vif)
                        continue;
                if (vif->type == NL80211_IFTYPE_STATION) {
                        bss = &vif->bss_conf;
                        break;
                }
        }
        if (!bss)
                return;
        /* CQM only for connected AP beacons, the RSSI is a weighted avg */
        if (bss->assoc && !(memcmp(bss->bssid, hdr->addr2, ETH_ALEN))) {
                if (ieee80211_is_beacon(hdr->frame_control))
                        rsi_perform_cqm(common, hdr->addr2, rxs->signal, vif);
        }

        return;
}

/**
 * rsi_indicate_pkt_to_os() - This function sends received packet to mac80211.
 * @common: Pointer to the driver private structure.
 * @skb: Pointer to the socket buffer structure.
 *
 * Return: None.
 */
void rsi_indicate_pkt_to_os(struct rsi_common *common,
                            struct sk_buff *skb)
{
        struct rsi_hw *adapter = common->priv;
        struct ieee80211_hw *hw = adapter->hw;
        struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);

        if ((common->iface_down) || (!adapter->sc_nvifs)) {
                dev_kfree_skb(skb);
                return;
        }

        /* filling in the ieee80211_rx_status flags */
        rsi_fill_rx_status(hw, skb, common, rx_status);

        ieee80211_rx_irqsafe(hw, skb);
}

static void rsi_set_min_rate(struct ieee80211_hw *hw,
                             struct ieee80211_sta *sta,
                             struct rsi_common *common)
{
        u8 band = hw->conf.chandef.chan->band;
        u8 ii;
        u32 rate_bitmap;
        bool matched = false;

        common->bitrate_mask[band] = sta->supp_rates[band];

        rate_bitmap = (common->fixedrate_mask[band] & sta->supp_rates[band]);

        if (rate_bitmap & 0xfff) {
                /* Find out the min rate */
                for (ii = 0; ii < ARRAY_SIZE(rsi_rates); ii++) {
                        if (rate_bitmap & BIT(ii)) {
                                common->min_rate = rsi_rates[ii].hw_value;
                                matched = true;
                                break;
                        }
                }
        }

        common->vif_info[0].is_ht = sta->ht_cap.ht_supported;

        if ((common->vif_info[0].is_ht) && (rate_bitmap >> 12)) {
                for (ii = 0; ii < ARRAY_SIZE(rsi_mcsrates); ii++) {
                        if ((rate_bitmap >> 12) & BIT(ii)) {
                                common->min_rate = rsi_mcsrates[ii];
                                matched = true;
                                break;
                        }
                }
        }

        if (!matched)
                common->min_rate = 0xffff;
}

/**
 * rsi_mac80211_sta_add() - This function notifies driver about a peer getting
 *                          connected.
 * @hw: pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @sta: Pointer to the ieee80211_sta structure.
 *
 * Return: 0 on success, negative error codes on failure.
 */
static int rsi_mac80211_sta_add(struct ieee80211_hw *hw,
                                struct ieee80211_vif *vif,
                                struct ieee80211_sta *sta)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        bool sta_exist = false;
        struct rsi_sta *rsta;
        int status = 0;

        rsi_dbg(INFO_ZONE, "Station Add: %pM\n", sta->addr);

        mutex_lock(&common->mutex);

        if ((vif->type == NL80211_IFTYPE_AP) ||
            (vif->type == NL80211_IFTYPE_P2P_GO)) {
                u8 cnt;
                int sta_idx = -1;
                int free_index = -1;

                /* Check if max stations reached */
                if (common->num_stations >= common->max_stations) {
                        rsi_dbg(ERR_ZONE, "Reject: Max Stations exists\n");
                        status = -EOPNOTSUPP;
                        goto unlock;
                }
                for (cnt = 0; cnt < common->max_stations; cnt++) {
                        rsta = &common->stations[cnt];

                        if (!rsta->sta) {
                                if (free_index < 0)
                                        free_index = cnt;
                                continue;
                        }
                        if (!memcmp(rsta->sta->addr, sta->addr, ETH_ALEN)) {
                                rsi_dbg(INFO_ZONE, "Station exists\n");
                                sta_idx = cnt;
                                sta_exist = true;
                                break;
                        }
                }
                if (!sta_exist) {
                        if (free_index >= 0)
                                sta_idx = free_index;
                }
                if (sta_idx < 0) {
                        rsi_dbg(ERR_ZONE,
                                "%s: Some problem reaching here...\n",
                                __func__);
                        status = -EINVAL;
                        goto unlock;
                }
                rsta = &common->stations[sta_idx];
                rsta->sta = sta;
                rsta->sta_id = sta_idx;
                for (cnt = 0; cnt < IEEE80211_NUM_TIDS; cnt++)
                        rsta->start_tx_aggr[cnt] = false;
                for (cnt = 0; cnt < IEEE80211_NUM_TIDS; cnt++)
                        rsta->seq_start[cnt] = 0;
                if (!sta_exist) {
                        rsi_dbg(INFO_ZONE, "New Station\n");

                        /* Send peer notify to device */
                        rsi_dbg(INFO_ZONE, "Indicate bss status to device\n");
                        rsi_inform_bss_status(common, RSI_OPMODE_AP, 1,
                                              sta->addr, sta->wme, sta->aid,
                                              sta, sta_idx, 0, vif);

                        if (common->key) {
                                struct ieee80211_key_conf *key = common->key;

                                if ((key->cipher == WLAN_CIPHER_SUITE_WEP104) ||
                                    (key->cipher == WLAN_CIPHER_SUITE_WEP40))
                                        rsi_hal_load_key(adapter->priv,
                                                         key->key,
                                                         key->keylen,
                                                         RSI_PAIRWISE_KEY,
                                                         key->keyidx,
                                                         key->cipher,
                                                         sta_idx,
                                                         vif);
                        }

                        common->num_stations++;
                }
        }

        if ((vif->type == NL80211_IFTYPE_STATION) ||
            (vif->type == NL80211_IFTYPE_P2P_CLIENT)) {
                rsi_set_min_rate(hw, sta, common);
                if (sta->ht_cap.ht_supported) {
                        common->vif_info[0].is_ht = true;
                        common->bitrate_mask[NL80211_BAND_2GHZ] =
                                        sta->supp_rates[NL80211_BAND_2GHZ];
                        if ((sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_20) ||
                            (sta->ht_cap.cap & IEEE80211_HT_CAP_SGI_40))
                                common->vif_info[0].sgi = true;
                        ieee80211_start_tx_ba_session(sta, 0, 0);
                }
        }

unlock:
        mutex_unlock(&common->mutex);

        return status;
}

/**
 * rsi_mac80211_sta_remove() - This function notifies driver about a peer
 *                             getting disconnected.
 * @hw: Pointer to the ieee80211_hw structure.
 * @vif: Pointer to the ieee80211_vif structure.
 * @sta: Pointer to the ieee80211_sta structure.
 *
 * Return: 0 on success, negative error codes on failure.
 */
static int rsi_mac80211_sta_remove(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif,
                                   struct ieee80211_sta *sta)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        struct ieee80211_bss_conf *bss = &vif->bss_conf;
        struct rsi_sta *rsta;

        rsi_dbg(INFO_ZONE, "Station Remove: %pM\n", sta->addr);

        mutex_lock(&common->mutex);

        if ((vif->type == NL80211_IFTYPE_AP) ||
            (vif->type == NL80211_IFTYPE_P2P_GO)) {
                u8 sta_idx, cnt;

                /* Send peer notify to device */
                rsi_dbg(INFO_ZONE, "Indicate bss status to device\n");
                for (sta_idx = 0; sta_idx < common->max_stations; sta_idx++) {
                        rsta = &common->stations[sta_idx];

                        if (!rsta->sta)
                                continue;
                        if (!memcmp(rsta->sta->addr, sta->addr, ETH_ALEN)) {
                                rsi_inform_bss_status(common, RSI_OPMODE_AP, 0,
                                                      sta->addr, sta->wme,
                                                      sta->aid, sta, sta_idx,
                                                      0, vif);
                                rsta->sta = NULL;
                                rsta->sta_id = -1;
                                for (cnt = 0; cnt < IEEE80211_NUM_TIDS; cnt++)
                                        rsta->start_tx_aggr[cnt] = false;
                                if (common->num_stations > 0)
                                        common->num_stations--;
                                break;
                        }
                }
                if (sta_idx >= common->max_stations)
                        rsi_dbg(ERR_ZONE, "%s: No station found\n", __func__);
        }

        if ((vif->type == NL80211_IFTYPE_STATION) ||
            (vif->type == NL80211_IFTYPE_P2P_CLIENT)) {
                /* Resetting all the fields to default values */
                memcpy((u8 *)bss->bssid, (u8 *)sta->addr, ETH_ALEN);
                bss->qos = sta->wme;
                common->bitrate_mask[NL80211_BAND_2GHZ] = 0;
                common->bitrate_mask[NL80211_BAND_5GHZ] = 0;
                common->min_rate = 0xffff;
                common->vif_info[0].is_ht = false;
                common->vif_info[0].sgi = false;
                common->vif_info[0].seq_start = 0;
                common->secinfo.ptk_cipher = 0;
                common->secinfo.gtk_cipher = 0;
                if (!common->iface_down)
                        rsi_send_rx_filter_frame(common, 0);
        }
        mutex_unlock(&common->mutex);
        
        return 0;
}

/**
 * rsi_mac80211_set_antenna() - This function is used to configure
 *                              tx and rx antennas.
 * @hw: Pointer to the ieee80211_hw structure.
 * @tx_ant: Bitmap for tx antenna
 * @rx_ant: Bitmap for rx antenna
 *
 * Return: 0 on success, Negative error code on failure.
 */
static int rsi_mac80211_set_antenna(struct ieee80211_hw *hw,
                                    u32 tx_ant, u32 rx_ant)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;
        u8 antenna = 0;

        if (tx_ant > 1 || rx_ant > 1) {
                rsi_dbg(ERR_ZONE,
                        "Invalid antenna selection (tx: %d, rx:%d)\n",
                        tx_ant, rx_ant);
                rsi_dbg(ERR_ZONE,
                        "Use 0 for int_ant, 1 for ext_ant\n");
                return -EINVAL; 
        }

        rsi_dbg(INFO_ZONE, "%s: Antenna map Tx %x Rx %d\n",
                        __func__, tx_ant, rx_ant);

        mutex_lock(&common->mutex);

        antenna = tx_ant ? ANTENNA_SEL_UFL : ANTENNA_SEL_INT;
        if (common->ant_in_use != antenna)
                if (rsi_set_antenna(common, antenna))
                        goto fail_set_antenna;

        rsi_dbg(INFO_ZONE, "(%s) Antenna path configured successfully\n",
                tx_ant ? "UFL" : "INT");

        common->ant_in_use = antenna;
        
        mutex_unlock(&common->mutex);
        
        return 0;

fail_set_antenna:
        rsi_dbg(ERR_ZONE, "%s: Failed.\n", __func__);
        mutex_unlock(&common->mutex);
        return -EINVAL;
}

/**
 * rsi_mac80211_get_antenna() - This function is used to configure 
 *                              tx and rx antennas.
 *
 * @hw: Pointer to the ieee80211_hw structure.
 * @tx_ant: Bitmap for tx antenna
 * @rx_ant: Bitmap for rx antenna
 * 
 * Return: 0 on success, negative error codes on failure.
 */
static int rsi_mac80211_get_antenna(struct ieee80211_hw *hw,
                                    u32 *tx_ant, u32 *rx_ant)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);

        *tx_ant = (common->ant_in_use == ANTENNA_SEL_UFL) ? 1 : 0;
        *rx_ant = 0;

        mutex_unlock(&common->mutex);
        
        return 0;       
}

static int rsi_map_region_code(enum nl80211_dfs_regions region_code)
{
        switch (region_code) {
        case NL80211_DFS_FCC:
                return RSI_REGION_FCC;
        case NL80211_DFS_ETSI:
                return RSI_REGION_ETSI;
        case NL80211_DFS_JP:
                return RSI_REGION_TELEC;
        case NL80211_DFS_UNSET:
                return RSI_REGION_WORLD;
        }
        return RSI_REGION_WORLD;
}

static void rsi_reg_notify(struct wiphy *wiphy,
                           struct regulatory_request *request)
{
        struct ieee80211_supported_band *sband;
        struct ieee80211_channel *ch;
        struct ieee80211_hw *hw = wiphy_to_ieee80211_hw(wiphy);
        struct rsi_hw * adapter = hw->priv; 
        struct rsi_common *common = adapter->priv;
        int i;
        
        mutex_lock(&common->mutex);

        rsi_dbg(INFO_ZONE, "country = %s dfs_region = %d\n",
                request->alpha2, request->dfs_region);

        if (common->num_supp_bands > 1) {
                sband = wiphy->bands[NL80211_BAND_5GHZ];

                for (i = 0; i < sband->n_channels; i++) {
                        ch = &sband->channels[i];
                        if (ch->flags & IEEE80211_CHAN_DISABLED)
                                continue;

                        if (ch->flags & IEEE80211_CHAN_RADAR)
                                ch->flags |= IEEE80211_CHAN_NO_IR;
                }
        }
        adapter->dfs_region = rsi_map_region_code(request->dfs_region);
        rsi_dbg(INFO_ZONE, "RSI region code = %d\n", adapter->dfs_region);
        
        adapter->country[0] = request->alpha2[0];
        adapter->country[1] = request->alpha2[1];

        mutex_unlock(&common->mutex);
}

static void rsi_mac80211_rfkill_poll(struct ieee80211_hw *hw)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        mutex_lock(&common->mutex);
        if (common->fsm_state != FSM_MAC_INIT_DONE)
                wiphy_rfkill_set_hw_state(hw->wiphy, true);
        else
                wiphy_rfkill_set_hw_state(hw->wiphy, false);
        mutex_unlock(&common->mutex);
}

static void rsi_resume_conn_channel(struct rsi_common *common)
{
        struct rsi_hw *adapter = common->priv;
        struct ieee80211_vif *vif;
        int cnt;

        for (cnt = 0; cnt < RSI_MAX_VIFS; cnt++) {
                vif = adapter->vifs[cnt];
                if (!vif)
                        continue;

                if ((vif->type == NL80211_IFTYPE_AP) ||
                    (vif->type == NL80211_IFTYPE_P2P_GO)) {
                        rsi_switch_channel(adapter, vif);
                        break;
                }
                if (((vif->type == NL80211_IFTYPE_STATION) ||
                     (vif->type == NL80211_IFTYPE_P2P_CLIENT)) &&
                    vif->bss_conf.assoc) {
                        rsi_switch_channel(adapter, vif);
                        break;
                }
        }
}

void rsi_roc_timeout(struct timer_list *t)
{
        struct rsi_common *common = from_timer(common, t, roc_timer);

        rsi_dbg(INFO_ZONE, "Remain on channel expired\n");

        mutex_lock(&common->mutex);
        ieee80211_remain_on_channel_expired(common->priv->hw);

        if (timer_pending(&common->roc_timer))
                del_timer(&common->roc_timer);

        rsi_resume_conn_channel(common);
        mutex_unlock(&common->mutex);
}

static int rsi_mac80211_roc(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                            struct ieee80211_channel *chan, int duration,
                            enum ieee80211_roc_type type)
{
        struct rsi_hw *adapter = (struct rsi_hw *)hw->priv;
        struct rsi_common *common = (struct rsi_common *)adapter->priv;
        int status = 0;

        rsi_dbg(INFO_ZONE, "***** Remain on channel *****\n");

        mutex_lock(&common->mutex);
        rsi_dbg(INFO_ZONE, "%s: channel: %d duration: %dms\n",
                __func__, chan->hw_value, duration);

        if (timer_pending(&common->roc_timer)) {
                rsi_dbg(INFO_ZONE, "Stop on-going ROC\n");
                del_timer(&common->roc_timer);
        }
        common->roc_timer.expires = msecs_to_jiffies(duration) + jiffies;
        add_timer(&common->roc_timer);

        /* Configure band */
        if (rsi_band_check(common, chan)) {
                rsi_dbg(ERR_ZONE, "Failed to set band\n");
                status = -EINVAL;
                goto out;
        }

        /* Configure channel */
        if (rsi_set_channel(common, chan)) {
                rsi_dbg(ERR_ZONE, "Failed to set the channel\n");
                status = -EINVAL;
                goto out;
        }

        common->roc_vif = vif;
        ieee80211_ready_on_channel(hw);
        rsi_dbg(INFO_ZONE, "%s: Ready on channel :%d\n",
                __func__, chan->hw_value);

out:
        mutex_unlock(&common->mutex);

        return status;
}

static int rsi_mac80211_cancel_roc(struct ieee80211_hw *hw,
                                   struct ieee80211_vif *vif)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        rsi_dbg(INFO_ZONE, "Cancel remain on channel\n");

        mutex_lock(&common->mutex);
        if (!timer_pending(&common->roc_timer)) {
                mutex_unlock(&common->mutex);
                return 0;
        }

        del_timer(&common->roc_timer);

        rsi_resume_conn_channel(common);
        mutex_unlock(&common->mutex);

        return 0;
}

#ifdef CONFIG_PM
static const struct wiphy_wowlan_support rsi_wowlan_support = {
        .flags = WIPHY_WOWLAN_ANY |
                 WIPHY_WOWLAN_MAGIC_PKT |
                 WIPHY_WOWLAN_DISCONNECT |
                 WIPHY_WOWLAN_GTK_REKEY_FAILURE  |
                 WIPHY_WOWLAN_SUPPORTS_GTK_REKEY |
                 WIPHY_WOWLAN_EAP_IDENTITY_REQ   |
                 WIPHY_WOWLAN_4WAY_HANDSHAKE,
};

static u16 rsi_wow_map_triggers(struct rsi_common *common,
                                struct cfg80211_wowlan *wowlan)
{
        u16 wow_triggers = 0;

        rsi_dbg(INFO_ZONE, "Mapping wowlan triggers\n");

        if (wowlan->any)
                wow_triggers |= RSI_WOW_ANY;
        if (wowlan->magic_pkt)
                wow_triggers |= RSI_WOW_MAGIC_PKT;
        if (wowlan->disconnect)
                wow_triggers |= RSI_WOW_DISCONNECT;
        if (wowlan->gtk_rekey_failure || wowlan->eap_identity_req ||
            wowlan->four_way_handshake)
                wow_triggers |= RSI_WOW_GTK_REKEY;

        return wow_triggers;
}

int rsi_config_wowlan(struct rsi_hw *adapter, struct cfg80211_wowlan *wowlan)
{
        struct rsi_common *common = adapter->priv;
        u16 triggers = 0;
        u16 rx_filter_word = 0;
        struct ieee80211_bss_conf *bss = NULL;

        rsi_dbg(INFO_ZONE, "Config WoWLAN to device\n");

        if (!adapter->vifs[0])
                return -EINVAL;

        bss = &adapter->vifs[0]->bss_conf;

        if (WARN_ON(!wowlan)) {
                rsi_dbg(ERR_ZONE, "WoW triggers not enabled\n");
                return -EINVAL;
        }

        common->wow_flags |= RSI_WOW_ENABLED;
        triggers = rsi_wow_map_triggers(common, wowlan);
        if (!triggers) {
                rsi_dbg(ERR_ZONE, "%s:No valid WoW triggers\n", __func__);
                return -EINVAL;
        }
        if (!bss->assoc) {
                rsi_dbg(ERR_ZONE,
                        "Cannot configure WoWLAN (Station not connected)\n");
                common->wow_flags |= RSI_WOW_NO_CONNECTION;
                return 0;
        }
        rsi_dbg(INFO_ZONE, "TRIGGERS %x\n", triggers);

        if (common->coex_mode > 1)
                rsi_disable_ps(adapter, adapter->vifs[0]);

        rsi_send_wowlan_request(common, triggers, 1);

        /**
         * Increase the beacon_miss threshold & keep-alive timers in
         * vap_update frame
         */
        rsi_send_vap_dynamic_update(common);

        rx_filter_word = (ALLOW_DATA_ASSOC_PEER | DISALLOW_BEACONS);
        rsi_send_rx_filter_frame(common, rx_filter_word);

        return 0;
}
EXPORT_SYMBOL(rsi_config_wowlan);

static int rsi_mac80211_suspend(struct ieee80211_hw *hw,
                                struct cfg80211_wowlan *wowlan)
{
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        rsi_dbg(INFO_ZONE, "%s: mac80211 suspend\n", __func__);
        mutex_lock(&common->mutex);
        if (rsi_config_wowlan(adapter, wowlan)) {
                rsi_dbg(ERR_ZONE, "Failed to configure WoWLAN\n");
                mutex_unlock(&common->mutex);
                return 1;
        }
        mutex_unlock(&common->mutex);

        return 0;
}

static int rsi_mac80211_resume(struct ieee80211_hw *hw)
{
        u16 rx_filter_word = 0;
        struct rsi_hw *adapter = hw->priv;
        struct rsi_common *common = adapter->priv;

        common->wow_flags = 0;

        rsi_dbg(INFO_ZONE, "%s: mac80211 resume\n", __func__);

        if (common->hibernate_resume) {
                common->mac_ops_resumed = true;
                /* Device need a complete restart of all MAC operations.
                 * returning 1 will serve this purpose.
                 */
                return 1;
        }

        mutex_lock(&common->mutex);
        rsi_send_wowlan_request(common, 0, 0);

        rx_filter_word = (ALLOW_DATA_ASSOC_PEER | ALLOW_CTRL_ASSOC_PEER |
                          ALLOW_MGMT_ASSOC_PEER);
        rsi_send_rx_filter_frame(common, rx_filter_word);
        mutex_unlock(&common->mutex);

        return 0;
}

#endif

static const struct ieee80211_ops mac80211_ops = {
        .tx = rsi_mac80211_tx,
        .start = rsi_mac80211_start,
        .stop = rsi_mac80211_stop,
        .add_interface = rsi_mac80211_add_interface,
        .remove_interface = rsi_mac80211_remove_interface,
        .config = rsi_mac80211_config,
        .bss_info_changed = rsi_mac80211_bss_info_changed,
        .conf_tx = rsi_mac80211_conf_tx,
        .configure_filter = rsi_mac80211_conf_filter,
        .set_key = rsi_mac80211_set_key,
        .set_rts_threshold = rsi_mac80211_set_rts_threshold,

        .set_bitrate_mask = rsi_mac80211_set_rate_mask,
        .ampdu_action = rsi_mac80211_ampdu_action,
        .sta_add = rsi_mac80211_sta_add,
        .sta_remove = rsi_mac80211_sta_remove,
        .set_antenna = rsi_mac80211_set_antenna,
        .get_antenna = rsi_mac80211_get_antenna,
        .rfkill_poll = rsi_mac80211_rfkill_poll,
        .remain_on_channel = rsi_mac80211_roc,
        .cancel_remain_on_channel = rsi_mac80211_cancel_roc,
#ifdef CONFIG_PM
        .suspend = rsi_mac80211_suspend,
        .resume  = rsi_mac80211_resume,
#endif
        .hw_scan = rsi_mac80211_hw_scan_start,
        .cancel_hw_scan = rsi_mac80211_cancel_hw_scan,
};

/**
 * rsi_mac80211_attach() - This function is used to initialize Mac80211 stack.
 * @common: Pointer to the driver private structure.
 *
 * Return: 0 on success, negative error codes on failure.
 */
int rsi_mac80211_attach(struct rsi_common *common)
{
        int status = 0;
        struct ieee80211_hw *hw = NULL;
        struct wiphy *wiphy = NULL;
        struct rsi_hw *adapter = common->priv;
        u8 addr_mask[ETH_ALEN] = {0x0, 0x0, 0x0, 0x0, 0x0, 0x3};

        rsi_dbg(INIT_ZONE, "%s: Performing mac80211 attach\n", __func__);

        hw = ieee80211_alloc_hw(sizeof(struct rsi_hw), &mac80211_ops);
        if (!hw) {
                rsi_dbg(ERR_ZONE, "%s: ieee80211 hw alloc failed\n", __func__);
                return -ENOMEM;
        }

        wiphy = hw->wiphy;

        SET_IEEE80211_DEV(hw, adapter->device);

        hw->priv = adapter;
        adapter->hw = hw;

        ieee80211_hw_set(hw, SIGNAL_DBM);
        ieee80211_hw_set(hw, HAS_RATE_CONTROL);
        ieee80211_hw_set(hw, AMPDU_AGGREGATION);
        ieee80211_hw_set(hw, SUPPORTS_PS);
        ieee80211_hw_set(hw, SUPPORTS_DYNAMIC_PS);

        hw->queues = MAX_HW_QUEUES;
        hw->extra_tx_headroom = RSI_NEEDED_HEADROOM;

        hw->max_rates = 1;
        hw->max_rate_tries = MAX_RETRIES;
        hw->uapsd_queues = RSI_IEEE80211_UAPSD_QUEUES;
        hw->uapsd_max_sp_len = IEEE80211_WMM_IE_STA_QOSINFO_SP_ALL;

        hw->max_tx_aggregation_subframes = RSI_MAX_TX_AGGR_FRMS;
        hw->max_rx_aggregation_subframes = RSI_MAX_RX_AGGR_FRMS;
        hw->rate_control_algorithm = "AARF";

        SET_IEEE80211_PERM_ADDR(hw, common->mac_addr);
        ether_addr_copy(hw->wiphy->addr_mask, addr_mask);

        wiphy->interface_modes = BIT(NL80211_IFTYPE_STATION) |
                                 BIT(NL80211_IFTYPE_AP) |
                                 BIT(NL80211_IFTYPE_P2P_DEVICE) |
                                 BIT(NL80211_IFTYPE_P2P_CLIENT) |
                                 BIT(NL80211_IFTYPE_P2P_GO);

        wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
        wiphy->retry_short = RETRY_SHORT;
        wiphy->retry_long  = RETRY_LONG;
        wiphy->frag_threshold = IEEE80211_MAX_FRAG_THRESHOLD;
        wiphy->rts_threshold = IEEE80211_MAX_RTS_THRESHOLD;
        wiphy->flags = 0;

        wiphy->available_antennas_rx = 1;
        wiphy->available_antennas_tx = 1;

        status = rsi_register_rates_channels(adapter, NL80211_BAND_2GHZ);
        if (status)
                return status;
        wiphy->bands[NL80211_BAND_2GHZ] =
                &adapter->sbands[NL80211_BAND_2GHZ];
        if (common->num_supp_bands > 1) {
                status = rsi_register_rates_channels(adapter,
                                                     NL80211_BAND_5GHZ);
                if (status)
                        return status;
                wiphy->bands[NL80211_BAND_5GHZ] =
                        &adapter->sbands[NL80211_BAND_5GHZ];
        }

        /* AP Parameters */
        wiphy->max_ap_assoc_sta = rsi_max_ap_stas[common->oper_mode - 1];
        common->max_stations = wiphy->max_ap_assoc_sta;
        rsi_dbg(ERR_ZONE, "Max Stations Allowed = %d\n", common->max_stations);
        hw->sta_data_size = sizeof(struct rsi_sta);

        wiphy->max_scan_ssids = RSI_MAX_SCAN_SSIDS;
        wiphy->max_scan_ie_len = RSI_MAX_SCAN_IE_LEN;
        wiphy->flags = WIPHY_FLAG_REPORTS_OBSS;
        wiphy->flags |= WIPHY_FLAG_AP_UAPSD;
        wiphy->features |= NL80211_FEATURE_INACTIVITY_TIMER;
        wiphy->reg_notifier = rsi_reg_notify;

#ifdef CONFIG_PM
        wiphy->wowlan = &rsi_wowlan_support;
#endif

        wiphy_ext_feature_set(wiphy, NL80211_EXT_FEATURE_CQM_RSSI_LIST);

        /* Wi-Fi direct parameters */
        wiphy->flags |= WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL;
        wiphy->flags |= WIPHY_FLAG_OFFCHAN_TX;
        wiphy->max_remain_on_channel_duration = 10000;
        hw->max_listen_interval = 10;
        wiphy->iface_combinations = rsi_iface_combinations;
        wiphy->n_iface_combinations = ARRAY_SIZE(rsi_iface_combinations);

        if (common->coex_mode > 1)
                wiphy->flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;

        status = ieee80211_register_hw(hw);
        if (status)
                return status;

        return rsi_init_dbgfs(adapter);
}